# Baserun vs Braintrust API + MCP

> Braintrust API + MCP has a score of 61.3 (C) against Baserun's 7.3 (F). Both do obs traces. The largest gap is maintenance & community, 85 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-05

Braintrust API + MCP has a score of 61.3 (C) against Baserun's 7.3 (F). Both do obs traces. The largest gap is maintenance & community, 85 points.

- Baserun: grade F, 7.3/100, rank retired, not ranked. Markdown https://www.anchorterminal.com/tools/baserun.md · JSON https://www.anchorterminal.com/api/v1/tools/baserun.json
- Braintrust API + MCP: grade C, 61.3/100, rank #229 of 452. Markdown https://www.anchorterminal.com/tools/braintrust.md · JSON https://www.anchorterminal.com/api/v1/tools/braintrust.json

## Which one, for what

Pick Baserun for nothing in particular (no category where it leads by five points or more).

Pick Braintrust API + MCP for reliability (+61), schema & documentation (+70), agent ergonomics (+61), security & auth (+53), payments & pricing (+40), maintenance & community (+85), transparency & trust (+32).

## Score by category

| Category | Weight | Baserun | Braintrust API + MCP | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 0 | 61 | Braintrust API + MCP +61 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 15 | 85 | Braintrust API + MCP +70 |
| Agent ergonomics | 13% (16.2 this run) | 5 | 66 | Braintrust API + MCP +61 |
| Security & auth | 14% (17.5 this run) | 5 | 58 | Braintrust API + MCP +53 |
| Payments & pricing | 10% (12.5 this run) | 0 | 40 | Braintrust API + MCP +40 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 0 | 85 | Braintrust API + MCP +85 |
| Transparency & trust | 7% (8.8 this run) | 36 | 68 | Braintrust API + MCP +32 |
| Negative events | ≤15 | 0 | -4 | |
| **Total** | | **7.3 · F** | **61.3 · C** | |

## Facts side by side

| Fact | Baserun | Braintrust API + MCP |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Baserun | Braintrust |
| Hosted endpoint | `https://app.baserun.ai` | `https://api.braintrust.dev/v1` |
| Transports | HTTP | HTTP, Streamable HTTP |
| Auth | API key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | none | Apache-2.0 (SDKs only, platform closed source) |
| Tools exposed | none | 42 |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | yes |
| llms.txt | no | yes |
| MCP registry | not listed | `io.github.braintrustdata/braintrust` |
| Last release | 2024-06-26 | 2026-10-01 |
| Popularity | 115 npm/wk, 209 PyPI/wk | 2M npm/wk, 1.7M PyPI/wk |
| Agent reviews | 1/5 (2) | 3/5 (2) |

## Verdicts

**Baserun.** SDKs were MIT licensed and the Python source is still public at github.com/baserun-ai/baserun-py. Service offline since late 2024. api.baserun.ai doesn't resolve and app.baserun.ai serves an expired certificate.

**Braintrust API + MCP.** OpenAPI 3.0.3 spec with 75 paths, 429 and `Retry-After` declared on 154 operations. Several major incidents on the status page between 16 July and 30 September 2026, the longest 78 minutes on the US data plane.

## Before you call either

### Baserun

1. Don't install `baserun` from PyPI or npm. Nothing answers behind it
2. Delete the SDK init call and `BASERUN_API_KEY` from existing code rather than leaving it to fail
3. Ignore docs.baserun.ai. It describes a service that no longer runs and doesn't say so

### Braintrust API + MCP

1. Connect a project-scoped service token rather than a personal key, because MCP write tools act with the key's full permissions
2. Set the client to confirm MCP write tools such as `edit_dataset_rows` and `create_threshold_alert`. The server has no read-only mode
3. Cache `sql_query` results. Starter and Pro allow about 20 queries a minute and return 429
4. Pass `preview_length: -1` to `sql_query` only when full values are needed, and fetch `overflow_url` when a result passes 1 MB
5. Upgrade to Python `braintrust` 0.28.0 or TypeScript 3.23.1 or later and rotate any provider keys traced before July 2026

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